U.S. patent application number 14/654651 was filed with the patent office on 2015-12-17 for stator for an electric machine.
The applicant listed for this patent is ROBERT BOSCH GMBH. Invention is credited to Christian Aumann.
Application Number | 20150364955 14/654651 |
Document ID | / |
Family ID | 49753197 |
Filed Date | 2015-12-17 |
United States Patent
Application |
20150364955 |
Kind Code |
A1 |
Aumann; Christian |
December 17, 2015 |
STATOR FOR AN ELECTRIC MACHINE
Abstract
The invention concerns a stator for an electric machine,
comprising a plate stack comprising a plurality of superposed
stator plates, the plate stack being delimited at the ends by cover
plates and an insulating plate being disposed on at least one cover
plate in the plate stack, the insulating plate interlocking with
the adjacent cover plate.
Inventors: |
Aumann; Christian;
(Stuttgart, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
ROBERT BOSCH GMBH |
Stuttgart |
|
DE |
|
|
Family ID: |
49753197 |
Appl. No.: |
14/654651 |
Filed: |
December 11, 2013 |
PCT Filed: |
December 11, 2013 |
PCT NO: |
PCT/EP2013/076286 |
371 Date: |
June 22, 2015 |
Current U.S.
Class: |
310/216.012 ;
310/216.017 |
Current CPC
Class: |
H02K 1/165 20130101;
H02K 3/38 20130101; H02K 1/146 20130101; H02K 2201/06 20130101;
H02K 3/522 20130101; H02K 1/18 20130101 |
International
Class: |
H02K 1/18 20060101
H02K001/18; H02K 1/16 20060101 H02K001/16; H02K 3/38 20060101
H02K003/38 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 21, 2012 |
DE |
10 2012 224 153.1 |
Claims
1. A stator for an electric machine, comprising a laminate stack
(2), including a plurality of stator laminations (11) positioned
one on top of the other, wherein the laminate stack (2) is
delimited at the end sides by covering laminations (6) and an
insulating lamination (3) is arranged on at least one covering
lamination (6) of the laminate stack (2), characterized in that the
insulating lamination (3) is connected in a form-fitting manner at
least to the covering lamination (6) which is directly
adjacent.
2. The stator as claimed in claim 1, characterized in that at least
one fixing bolt (9), which protrudes into an assigned cutout (7) in
the covering lamination (6), is arranged on the insulating
lamination (3).
3. The stator as claimed in claim 2, characterized in that the
fixing bolt (9) is formed integrally with the insulating lamination
(3).
4. The stator as claimed in claim 2, characterized in that the
cutout (7) is arranged in the covering lamination (6) with a
spacing from a circumferential side.
5. The stator as claimed in claim 2, characterized in that the
fixing bolt (9) protrudes into a cutout (7) in at least one further
stator lamination (11) which follows the covering lamination
(6).
6. The stator as claimed in claim 5, characterized in that the
cutout (7) in the further stator lamination (11) is open towards a
circumferential side.
7. The stator as claimed in claim 5, characterized in that the
cutout (7) in the further stator lamination (11) is in the form of
a slot with a longitudinal extent in a circumferential direction
which is greater than a dimension of the fixing bolt (9) in the
circumferential direction.
8. The stator as claimed in claim 2, characterized in that the
insulating lamination (3) is connected in a form-fitting manner, to
an interconnecting disk (4), which adjoins the laminate stack (2)
at an end side.
9. The stator as claimed in claim 8, characterized in that the
fixing bolt (9) has a first bolt section and a second bolt section
(9a, 9b), which protrude beyond the insulating lamination (3) on
its opposite end sides, wherein the first bolt section (9a)
protrudes into the cutout (7) in the covering lamination (6), and
the second bolt section (9b) protrudes into a cutout (7) in the
interconnecting disk (4).
10. The stator as claimed in claim 9, characterized in that the
cutout (7) in the interconnecting disk (4) is open radially
inwards.
11. The stator as claimed in claim 8, characterized in that the
first and second bolt sections (9a, 9b) are provided with clamping
ribs (10) on a circumference of the bolt sections (9a, 9b).
12. The stator as claimed in claim 1, characterized in that the
insulating lamination (3) is manufactured from plastic.
13. An electric machine comprising a stator (1) as claimed in claim
1, wherein the stator laminations (11) positioned one on top of the
other are arranged so as to be rotated through a specific angle
relative to one another with respect to a circumferential
direction, as a result of which stator teeth are formed, whose
longitudinal axis is arranged at an angle to the axis of rotation
of the rotor arranged in the stator.
14. The stator as claimed in claim 5, characterized in that the
cutout (7) in the further stator lamination (11) is in the form of
a slot with a longitudinal extent in a circumferential direction
which is greater than a dimension of the fixing bolt (9) in the
circumferential direction, and the cutouts (7) are arranged offset
with respect to one another in the circumferential direction.
15. The stator as claimed in claim 1, characterized in that the
insulating lamination (3) is connected integrally to an
interconnecting disk (4), which adjoins the laminate stack (2) at
the end side.
Description
BACKGROUND OF THE INVENTION
[0001] The invention relates to a stator for an electric
machine.
[0002] Stators for electric machines which are constructed from a
laminate stack which is formed from a plurality of stator
laminations including a sheet metal material which are positioned
one on top of the other are known. The laminate stack is delimited
at both opposite end sides by in each case one end or covering
lamination which is likewise manufactured from sheet metal and
which is adjoined by an insulating lamination including an
electrically insulating material. One of the insulating laminations
is connected on the side remote from the laminate stack to a
connection plate, via which coil windings which are accommodated in
the stator are connected to the power supply.
[0003] During fitting of the stator, first the laminate stack is
assembled from the individual laminations, then the winding is
performed in a winding machine. In this case, care should be taken
to ensure that the individual component parts of the stator
maintain their relative position with respect to one another.
SUMMARY OF THE INVENTION
[0004] The invention is based on the object of designing a stator
for an electric machine to be fitting friendly using simple design
measures.
[0005] The stator according to the invention is used in electric
machines, for example in drive motors, which are used in motor
vehicles or in hand held machine tools. The electric machine is,
for example, an internal rotor motor comprising an outer,
surrounding stator and an inner rotor.
[0006] The stator has a laminate stack, which includes a plurality
of individual stator laminations positioned one on top of the
other, which are manufactured, for example, from a sheet metal
material, in particular punched out of a metal sheet. The end side
laminations of the laminate stack form the end or covering
laminations, wherein an insulating lamination including an
electrically insulating material adjoins at least one covering
lamination. In the stator according to the invention, the
insulating lamination is connected in a form fitting manner at
least to the covering lamination which is directly adjacent. This
embodiment has the advantage that prefixing and positioning of the
individual parts of the laminate stack is provided so that, once
the stator laminations have been layered one on top of the other to
form the laminate stack and the insulating lamination has been
applied, a prefabricated structural unit is produced, which can be
supplied to the winding machine, wherein the risk of the individual
parts of the laminate stack becoming detached from one another
again is significantly reduced. The winding process, i.e. the
application of stator windings to stator teeth which are formed on
the laminate stack, can be performed in the winding machine. The
form fitting connection between the insulating lamination and the
adjacent covering lamination can be produced easily during
production of the laminate stack.
[0007] The form fitting connection is produced via a form fitting
connection element, for example a fixing bolt, which protrudes into
an assigned cutout. The fixing bolt is advantageously arranged on
the insulating lamination, and the cutout is introduced into the
covering lamination. The fixing bolt can possibly be formed
integrally with the insulating lamination, in particular in an
embodiment of the insulating lamination as plastic component part,
for example as plastic injection molded component part.
Furthermore, it is expedient to provide a plurality of fixing bolts
distributed over the circumference, which fixing bolts protrude
into assigned cutouts in the covering lamination. The connection
via the fixing bolt and the cutout is performed in the
circumferential direction and in the radial direction in a form
fitting manner, possibly also in the axial direction. The fixing
bolt can be inserted into the cutout with pressure, as a result of
which friction locking between the wall of the fixing bolt and the
wall sections adjoining the cutout is produced. In the case of a
deformation of the fixing bolt, in particular in the case where the
insulating lamination including the fixing bolt is formed from
plastic, a form fitting connection can also be produced in the
axial direction by a recess between the fixing bolt and the
cutout.
[0008] The cutout in the covering lamination is advantageously
produced by punching. Furthermore, it is expedient that the cutout
is arranged with a spacing with respect to the circumferential side
of the covering lamination, with the result that the cutout is
completely surrounded by material of the covering lamination. In
this way, a form fitting connection is achieved between the
insulating lamination and the covering lamination in all directions
orthogonal to the longitudinal axis.
[0009] In accordance with a further expedient embodiment, the
fixing bolt protrudes not only into the covering lamination, but
into a cutout in at least one further stator lamination, which
follows the covering lamination. Possibly, a plurality of stator
laminations following on directly from the covering lamination can
be provided with cutouts, which are aligned with the cutout in the
covering lamination and into which the fixing bolt protrudes. The
cutouts in the further stator laminations can be open towards the
circumferential side and are advantageously introduced by punching,
in the same way as the cutout in the covering lamination.
Furthermore, it is expedient that the cutout in the stator
lamination is in the form of a slot with a longitudinal extent in
the circumferential direction. In the case of angled stators, which
have coil windings running at an angle in relation to the stator
longitudinal axis, by virtue of the cutout being embodied as a
slot, account is taken of the angular shift between the covering
lamination and the following stator lamination(s). The embodiment
as a slot enables axial insertion of the fixing bolt despite the
angular offset between the successive laminations. The cutout in
the covering lamination, on the other hand, advantageously
corresponds to the cross section of the fixing bolt.
[0010] In accordance with a further expedient embodiment, the
insulating lamination is connected in a form fitting manner to an
interconnecting disk (connection plate) on the side remote from the
laminate stack, via which interconnecting disk power is supplied to
the coil windings in the stator. The insulating lamination is
therefore connected in a form fitting manner to the facing covering
lamination of the laminate stack in the region of an end side and
connected in a form fitting manner to the facing interconnecting
disk in the region of the opposite end side remote from the
covering lamination.
[0011] The connection to the interconnecting disk is performed via
a further form fitting connection element, which possibly coincides
with the fixing bolt. For example, the fixing bolt can have a first
and a second bolt section, which protrude beyond the insulating
lamination on opposite end sides, wherein the first bolt section
protrudes into the cutout in the covering lamination and the second
bolt section protrudes into a cutout which is introduced into the
interconnecting disk. Thus, a dual function is provided for the
fixing bolt, namely firstly the form fitting connection to the
covering lamination and secondly the form fitting connection to the
interconnecting disk.
[0012] The cutout in the interconnecting disk into which the bolt
section protrudes can be open radially inwards. Thus, there is a
form fitting connection radially outwards and in the
circumferential direction.
[0013] In order to improve the connection between the fixing bolt
and the cutout, clamping ribs can be arranged on the lateral
surface of the fixing bolt, said clamping ribs being inserted
axially into the cutout with pressure. Such pressing ribs can be
arranged both on the first and on the second bolt sections of the
fixing bolt.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Further advantages and expedient embodiments are set forth
in the further claims, the description of the figures and the
drawings, in which:
[0015] FIG. 1 shows a perspective view of a stator comprising a
laminate stack and an interconnecting disk positioned on the end
side,
[0016] FIG. 2 shows a laminate stack of the stator in a perspective
view,
[0017] FIG. 3 shows a detail of an insulating lamination, which is
arranged between the laminate stack and the interconnecting disk,
comprising a fixing bolt,
[0018] FIG. 4 shows the laminate stack comprising insulating
laminations arranged on both end sides, illustrated in a side
view,
[0019] FIG. 5 shows the laminate stack comprising insulating
laminations in a perspective view,
[0020] FIG. 6 shows a detailed illustration of a fixing bolt, which
protrudes into cutouts in the covering lamination or the stator
laminations following on therefrom,
[0021] FIG. 7 shows a sectional illustration of the fixing bolt,
which protrudes into the cutout in the covering lamination or the
stator laminations following on therefrom,
[0022] FIG. 8 shows a section transverse to the longitudinal axis
of the fixing bolt,
[0023] FIG. 9 shows the interconnecting disk in a perspective
detail illustration,
[0024] FIG. 10 shows a perspective view of an insulation lamination
and the interconnecting disk,
[0025] FIG. 11 shows, in plan view, the connection between a bolt
section of the fixing bolt on the insulating lamination and the
interconnecting disk,
[0026] FIG. 12 shows the connection between the fixing bolt and the
interconnecting disk in the section transverse to the bolt
longitudinal axis,
[0027] FIG. 13 shows the connection between the fixing bolt and the
interconnecting disk in the longitudinal section through the fixing
bolt.
[0028] Identical component parts have been provided with the same
reference symbols in the figures.
DETAILED DESCRIPTION
[0029] FIG. 1 shows a stator 1 for an electric machine, in
particular for an electric internal rotor motor. The stator 1 has a
stator stack or laminate stack 2, which is constructed from a
multiplicity of individual stator laminations which are stacked one
on top of the other. Furthermore, an interconnecting disk 4 is
arranged on the end side of the laminate stack 2, via which
interconnecting disk power is supplied to windings 5 in the
laminate stack 2. An insulating lamination 3, which includes an
electrically insulating material in particular of plastic, is
arranged between the laminate stack 2 and the interconnecting disk
4. The insulating lamination 3 can be in the form of a plastic
injection molded component part. A corresponding insulating
lamination is also located on the opposite axial end side of the
laminate stack 2.
[0030] The laminate stack 2 is angled and has carrier teeth
pointing radially inwards, with the windings 5 being laid around
said carrier teeth. Owing to the angled arrangement, the windings 5
extend at an angle to the stator longitudinal axis.
[0031] FIG. 2 shows the laminate stack 2 in a perspective detail
illustration. The laminate stack includes a multiplicity of stator
laminations layered one on top of the other, wherein the end side
terminating laminations form the end or covering laminations 6.
Each lamination of the laminate stack is punched out of a metal
sheet and has an outer carrier ring, on which carrier teeth formed
integrally for accommodating the windings extend radially
inwards.
[0032] In total three cutouts 7, distributed uniformly over the
circumference, are introduced into the covering laminations 6, said
cutouts having a round cross section and being arranged at a
spacing with respect to the circumferential side. The cutouts 7 are
located completely within the covering laminations 6. Further
cutouts or recesses 8 in the directly adjacent stator laminations
correspond to the cutouts 7; the recesses 8 are open towards the
circumferential side and are axially aligned with the cutouts 7 in
the end side covering laminations 6. The recesses 8 have, when
viewed in the plane of the laminations, a slot shape with a
longitudinal extent in the circumferential direction. This makes it
possible for an axially continuous opening to be formed between the
covering lamination 6 and the directly adjacent stator laminations
despite the angular offset between the various stator laminations.
This axial opening is used for receiving a form fitting connection
element, which is arranged on the insulating lamination.
[0033] Such a form fitting connection element is illustrated in
FIG. 3, which shows a detail of an insulating lamination 3. The
form fitting connection element is formed by a fixing bolt 9, which
is formed integrally with the insulating lamination 3 and has a
lower bolt section 9a and an upper bolt section 9b, wherein the
lower bolt section 9a protrudes beyond the lower end side of the
insulating lamination 3. The upper bolt section 9b can possibly
protrude beyond the upper end side of the insulating lamination 3
or protrude upwards at least beyond the directly surrounding
sections of the insulating lamination. This makes it possible for
the lower bolt section 9a to be inserted into the cutouts or
recesses 7, 8 in the covering lamination 6 or the adjoining stator
laminations and for the upper bolt section 9b to be inserted into
associated cutouts in the interconnecting disk 4. In this way, a
form fitting connection can be produced, firstly between the
insulating lamination 3 and the laminate stack 2 and secondly
between the insulating lamination 3 and the interconnecting disk
4.
[0034] Clamping ribs 10 which extend in the axial direction of the
fixing bolt are arranged on the lateral surface of the fixing bolt
9. In each case clamping ribs 10 are arranged both on the lower
bolt section 9a and on the upper bolt section 9b. The lower bolt
section 9a, which engages in the cutouts 7 and 8 in the laminations
of the laminate stack, has a smaller outer diameter than the upper
bolt section 9b, which is intended for engagement in assigned
cutouts in the interconnecting plate 4.
[0035] The laminate stack 2 comprising insulating laminations 3 on
both end sides is illustrated in FIGS. 4 and 5. The perspective
illustration shown in FIG. 5 shows that in total three fixing bolts
9 are arranged, distributed over the circumference, on the
insulating lamination 3. Corresponding cutouts for receiving the
fixing bolts 9 are introduced into the stator laminations including
the covering laminations 6.
[0036] FIG. 6 and FIG. 7 show the engagement of the fixing bolt 9
in the cutout 7 in the covering lamination 6 and the cutouts or
recesses 8 in three stator laminations 11 directly adjacent to the
covering lamination 6. The cutouts 8 in the stator laminations 11
are open towards the circumferential side, whereas the cutout 7 in
the covering lamination 6 has a circumferential, closed wall; the
cutout 7 is located at a spacing with respect to the
circumferential side of the covering lamination.
[0037] The sectional illustration shown in FIG. 8 shows that the
clamping ribs 10, which are arranged on the lateral surface of the
fixing bolt 9 and protrude radially beyond the lateral surface,
bear against that wall of the covering lamination 6 which adjoins
the cutout 7, in the inserted state. In total three clamping ribs
10 are arranged, distributed over the circumference, on the lateral
surface of the fixing bolt 9, wherein the clamping ribs extend in
the direction of the longitudinal axis of the fixing bolt.
[0038] FIG. 9 shows an interconnecting disk 4 in a perspective
detail illustration. It can be seen that in total three cutouts 12
are introduced into the interconnecting disk 4, distributed over
the circumference in the region of an end side, wherein the cutouts
12 are open radially inwards. The cutouts 12 are used for receiving
the upper bolt section 9b of the fixing bolt 9. That end side of
the interconnecting disk 4 which points upwards in FIG. 9 points
downwards in the illustrations in FIGS. 1 and 10 and faces the
insulating lamination.
[0039] FIG. 10 illustrates the insulating laminations 3 and the
interconnecting plate 4 in the connected state. That section of the
fixing bolt 9 which protrudes downwards beyond the end side is used
for engagement in the assigned cutouts in the laminate stack
therebeneath.
[0040] The detail illustrations in FIGS. 11 and 12 show the
engagement of the bolt section of the fixing bolt 9 in the cutout
12 in the interconnecting disk 4. The cutout 12 is approximately
semicircular, and the clamping ribs 10 on the bolt section of the
fixing bolt 9 extend over an angular segment of less than
180.degree. on the lateral surface of the fixing bolt.
[0041] FIG. 13 shows a longitudinal section through the fixing bolt
9, which is in engagement with the cutout 12 in the interconnecting
plate 4. The upper section 9b of the fixing bolt 9 protrudes into
the cutout 12 in the interconnecting plate 4, wherein the clamping
ribs 10 on the outer lateral surface are pressed together so that
the fixing bolt 9 rests in the cutout 12 with a radial pressing
force.
* * * * *